94 CONTRIBUTIONS TO MINERALOGY. [bull.262 
associated minerals are tourmaline, quartz, feldspar, museovite, bio 
tite, chrysoberyl, apatite, garnet, and chlorite. 
NORWAY. 
The mineral is found at Tvedestrand in minute fibers in cordieriti 
gneiss. The pleochroism is as follows: 
JC = fr, pale yellow, almost colorless. 
a, intense cobalt blue. 
Cross sections show a prismatic angle of about 60°. The birefrin 
gence (.010) is feeble. Pleochroic halos (in }^ellow) are very character 
istic. The axial angle (2V) is about 35°, and the dispersion strong 
p ~>v. The associated minerals are cordierite and sillimanite. 
Romberg has described a mineral from Argentina (2.51 per cen 
B 2 3 ) which seems to resemble the California dumortierite. The colo 
is lilac and the pleochroism similar to that from California. 
* UNITED STATES. 
NEW YORK. 
The mineral occurs in that part of New York City known as Hal 
lem. It has been sparingly found as acicular crystals " aggregated ii 
fasces or tufts resembling clippings of hair" in a lode of red granil 
extending southeastward from Fourth avenue and One hundred ai 
twenty-third street to Madison avenue at One hundred and sixteent 
street. At One hundred and seventy -first street and Fort Washingtc 
avenue it was found in several pockets in a vein of coarse pegmati 
in mica-schist. The vein is about 3 feet wide and the pockets extendi 
for about 80 feet. The body of the vein is granular gray quartz, orth 
clase, and flaky museovite. The dumortierite occurs chiefly in tl 
orthoclase, though it has also been found as long, filiform inclusio 
in the museovite, singly and radiating from centers. It has also beoi 
noticed at Kips Bay, near the upper end of Riverside Park, in whii 
oligoclase, and at Tenth avenue and One hundred and thirtieth stre< 
The associated minerals are orthoclase, quartz, museovite, xenotiu 
monazite, tourmaline, zircon, torbernite (?), antunite (?), apatite, gi 
net, and andalusite. 
A brief study of several slides of the New York City dumortier 
showed that the mineral occurs almost entirely in the orthocla; 
Very rarely is it in the quartz or museovite. It is usually in fibre 
forms, with ragged outlines, and in one particular section an ortl 
clase crystal was filled with minute threads of dumortierite, arrani.ii 
more or less parallel. In these slides andalusite also was noticed. 
Mr. Frederick Braun, of Brooklyn, N. Y., very kindly lent 
writer his private collection of New York dumortierite, which pr 
ably contains the finest dumortierite specimens ever found in t 
